Features: 1.No battery self-generation, just press the button and kinetic energy will be converted into electric energy (Pressing force is stronger than that of traditional doorbells to ensure sufficient generated energy). 2.Adjustable 4?level high volumes and optional 32 ringtones. 3.Large button design with long lifespan, sensitive and convenient to use. 4.Long-distance wireless working range, can reach a maximum value of 550in in open and batter free environments. 5.IP47 waterproof and dustproof, no worry about wind and rain. Specification: Features:_x000D_ _x000D_ No battery self-generation, just press the button and kinetic energy will be converted into electric energy (Pressing force is stronger than that of traditional doorbells to ensure sufficient generated energy). _x000D_ Adjustable 4-level high volumes and optional 32 ringtones. _x000D_ Large button design with long lifespan, sensitive and convenient to use. _x000D_ Long-distance wireless working range, can reach a maximum value of 550in in open and batter free environments. _x000D_ IP47 waterproof and dustproof, no worry about wind and rain. _x000D_ Quick and easy installation without requiring wiring. _x000D_ _x000D_ Installation Steps:_x000D_ 1. Plug the doorbell host into the jack._x000D_ 2. Tear off the double-sided tape on the back of the doorbell button._x000D_ 3. Install the doorbell button on the door and the installation is completed._x000D_ _x000D_ Specification:_x000D_ Condition: 100% Brand New_x000D_ Material: ABS_x000D_ Plug Type: US 110-240V_x000D_ Power Supply: AC 110-240V_x000D_ Optional Type: 1*transmitter+1*receiver, 2*transmitter+1*receiver_x000D_ No. of Music: 32_x000D_ Waterproof Level: IP47_x000D_ LED lights Mode: light off, chime+flash, flashlight_x000D_ Optional Package Weight: Approx.155g/6.1oz or 240g/9.4oz_x000D_ _x000D_ Package List:_x000D_ 1 * Wireless Plug-in Receiver_x000D_ 2 * Self-powered Transmitter_x000D_ _x000D_ _x000D_ _x000D_ Note:_x000D_ Please note that the new type and old type of this product will be sent randomly, and make sure you will not mind before ordering.